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INFO: rcu detected stall in ip_list_rcv

Status: upstream: reported on 2025/12/04 02:09
Reported-by: syzbot+70204a71afdd800448da@syzkaller.appspotmail.com
First crash: 89d, last: 16d
▶ ▼ Similar bugs (16)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: soft lockup in ip_list_rcv (2) kvm 1 8 1407d 1407d 0/29 auto-closed as invalid on 2022/06/25 08:42
linux-6.1 INFO: rcu detected stall in ip_list_rcv (2) 1 1 399d 399d 0/3 auto-obsoleted due to no activity on 2025/05/08 11:17
linux-5.15 INFO: rcu detected stall in ip_list_rcv 1 2 535d 591d 0/3 auto-obsoleted due to no activity on 2024/12/22 19:35
linux-6.1 INFO: rcu detected stall in ip_list_rcv 1 1 551d 551d 0/3 auto-obsoleted due to no activity on 2024/12/06 18:02
linux-5.15 INFO: rcu detected stall in ip_list_rcv (2) 1 2 51d 130d 0/3 upstream: reported on 2025/10/23 22:28
upstream INFO: rcu detected stall in ip_list_rcv (6) net 1 C done done 56 29d 820d 0/29 upstream: reported C repro on 2023/12/04 09:45
upstream INFO: rcu detected stall in ip_list_rcv (5) lsm netfilter 1 3 963d 1021d 0/29 auto-obsoleted due to no activity on 2023/10/11 22:12
upstream INFO: rcu detected stall in ip_list_rcv net 1 C error done 3 1980d 2006d 15/29 fixed on 2020/11/16 12:12
upstream INFO: rcu detected stall in ip_list_rcv (4) netfilter 1 1 1338d 1338d 0/29 auto-closed as invalid on 2022/09/01 16:20
upstream INFO: rcu detected stall in ip_list_rcv (2) netfilter 1 3 1835d 1914d 0/29 auto-closed as invalid on 2021/05/23 12:59
linux-6.1 INFO: rcu detected stall in ip_list_rcv (3) 1 1 171d 171d 0/3 auto-obsoleted due to no activity on 2025/12/22 08:55
upstream INFO: rcu detected stall in ip_list_rcv (3) net 1 1 1527d 1527d 0/29 closed as invalid on 2022/02/08 10:10
android-5-15 BUG: soft lockup in ip_list_rcv 1 20 525d 679d 0/2 auto-obsoleted due to no activity on 2024/12/22 22:06
android-6-1 BUG: soft lockup in ip_list_rcv 1 2 577d 600d 0/2 auto-obsoleted due to no activity on 2024/10/31 19:10
android-5-15 BUG: soft lockup in ip_list_rcv (2) 1 1 342d 342d 0/2 auto-obsoleted due to no activity on 2025/06/24 13:43
android-5-10 BUG: soft lockup in ip_list_rcv 1 1 573d 573d 0/2 auto-obsoleted due to no activity on 2024/11/04 20:30

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 13595 jiffies s: 29309 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10579 Comm: syz.5.969 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:memset_orig+0x75/0xac arch/x86/lib/memset_64.S:90
Code: 89 47 30 48 89 47 38 48 8d 7f 40 75 d8 0f 1f 84 00 00 00 00 00 89 d1 83 e1 38 74 14 c1 e9 03 66 0f 1f 44 00 00 ff c9 48 89 07 <48> 8d 7f 08 75 f5 83 e2 07 74 0a ff ca 88 07 48 8d 7f 01 75 f6 4c
RSP: 0018:ffffc90000006918 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004
RDX: 0000000000000038 RSI: 0000000000000000 RDI: ffffc90000006970
RBP: ffffc90000006a28 R08: ffffc90000006997 R09: 0000000000000000
R10: ffffc90000006960 R11: fffff52000000d33 R12: ffffc90000006960
R13: ffffc90000006c00 R14: ffff88807be0edb0 R15: 1ffff92000000d28
FS:  00007f3f904816c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000001 CR3: 0000000064d0f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __perf_event_output kernel/events/core.c:7965 [inline]
 perf_event_output_forward+0x244/0x3e0 kernel/events/core.c:7993
 __perf_event_overflow+0x447/0x630 kernel/events/core.c:9718
 perf_swevent_overflow kernel/events/core.c:9794 [inline]
 perf_swevent_event+0x324/0x630 kernel/events/core.c:-1
 perf_tp_event+0x54f/0x1450 kernel/events/core.c:10344
 perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10268
 perf_trace_preemptirq_template+0x269/0x330 include/trace/events/preemptirq.h:14
 trace_irq_enable+0xbb/0xe0 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:56
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:tcp_v4_rcv+0x11aa/0x2af0 net/ipv4/tcp_ipv4.c:2047
Code: 74 24 40 4c 8b 7c 24 48 4c 8b 6c 24 28 48 8b 44 24 18 48 8d 58 12 48 89 d8 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 d2 0a 00 00 <0f> b6 1b bf 06 00 00 00 89 de e8 e7 b6 7e f8 83 fb 06 0f 85 fe 05
RSP: 0018:ffffc90000007020 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88807cd0a4d2 RCX: ffff888029fe1e00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007228 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000df0 R12: dffffc0000000000
R13: ffff88802d46d000 R14: ffff888061b3804e R15: ffff888061b38062
 ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2ca/0x510 net/ipv4/ip_input.c:233
 NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304
 dst_input include/net/dst.h:477 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
 ip_sublist_rcv+0xa4c/0xd70 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3f2/0x440 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5664 [inline]
 __netif_receive_skb_list_core+0x583/0x750 net/core/dev.c:5712
 __netif_receive_skb_list net/core/dev.c:5764 [inline]
 netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5855
 gro_normal_list include/net/gro.h:451 [inline]
 gro_normal_one include/net/gro.h:464 [inline]
 napi_skb_finish net/core/gro.c:575 [inline]
 napi_gro_receive+0x565/0xb00 net/core/gro.c:605
 receive_buf+0x2203/0x3820 drivers/net/virtio_net.c:1870
 virtnet_receive drivers/net/virtio_net.c:2155 [inline]
 virtnet_poll+0x5dd/0x1280 drivers/net/virtio_net.c:2229
 __napi_poll+0xc0/0x460 net/core/dev.c:6625
 napi_poll net/core/dev.c:6692 [inline]
 net_rx_action+0x616/0xc40 net/core/dev.c:6828
 handle_softirqs+0x280/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:finish_task_switch+0x33d/0x8f0 kernel/sched/core.c:5293
Code: 0f 85 93 01 00 00 4c 89 ff be 04 00 00 00 e8 ea dc 81 00 f0 41 ff 0f 0f 84 a4 00 00 00 81 7d a8 80 00 00 00 0f 84 ac 00 00 00 <48> 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 4c 89 e7 e8 2c 2f ff
RSP: 0018:ffffc9000492f8f8 EFLAGS: 00000206
RAX: 1ffff110053fc401 RBX: ffff888029fe3458 RCX: ffffffff815d61a6
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff888078fd8980
RBP: ffffc9000492f950 R08: ffff888078fd8983 R09: 1ffff1100f1fb130
R10: dffffc0000000000 R11: ffffed100f1fb131 R12: ffff888029fe2340
R13: dffffc0000000000 R14: ffff8880187dda00 R15: ffff888078fd8980
 context_switch kernel/sched/core.c:5384 [inline]
 __schedule+0x155b/0x45a0 kernel/sched/core.c:6700
 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867
 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x40/0x50 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1068/0x13f0 kernel/signal.c:2867
 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3f8f59bf79
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3f90481028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 000000000000000b RBX: 00007f3f8f815fa0 RCX: 00007f3f8f59bf79
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140
RBP: 00007f3f8f6327e0 R08: 0000000000000002 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3f8f816038 R14: 00007f3f8f815fa0 R15: 00007ffe656cece8
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/15 10:26 linux-6.6.y 1b4ef5214f17 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in ip_list_rcv
2025/12/04 02:08 linux-6.6.y 4791134e4aeb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan-perf INFO: rcu detected stall in ip_list_rcv
* Struck through repros no longer work on HEAD.